CALIFORNIA 
AGRICULTURAL  EXTENSION  SERVICE 

CIRCULAR  21 

AUGUST,  1928 


BOVINE  TUBERCULOSIS 


C.  M.  HARING  and  J.  TRAUM 


PUBLISHED   BY 

THE  COLLEGE  OF  AGRICULTURE 
UNIVERSITY  OF  CALIFORNIA 

Cooperative  Extension  work  in  Agriculture  and  Home  Economics,  College  of  Agriculture, 
University  of  California,  and  United  States  Department  of  Agriculture  cooperating.  Dis- 
tributed in  furtherance  of  the  Acts  of  Congress  of  May  8  and  June  30,  1914.  B.  H.  Crocheron, 
Director,  California  Agricultural  Extension  Service. 

UNIVERSITY  OF  CALIFORNIA  PRINTING  OFFICE 

BERKELEY,  CALIFORNIA 

1928 


Digitized  by  the  Internet  Archive 

in  2011  with  funding  from 

University  of  California,  Davis  Libraries 


http://www.archive.org/details/bovinetuberculos21hari 


BOVINE  TUBERCULOSIS 

C.  M.  HARINGi  AND  J.  TRAUM2 


All  species  of  domestic  animals  are  susceptible  to  tuberculosis, 
but  the  disease  is  more  prevalent  in  cattle,  hogs  and  poultry  than  in 
other  farm  animals.  Tuberculosis  is  readily  transmitted  from  one 
individual  to  another  of  the  same  species  by  direct  or  indirect  contact. 
On  the  other  hand,  transmission  between  species  varies  because  of  the 
existence  of  three  more  or  less  distinct  types  of  tubercle  bacilli,  the 
human,  the  bovine  and  the  avian. 

In  general,  tuberculosis  found  in  cattle  is  induced  by  the  bovine 
tubercle  bacillus.  However,  local,  non-progressive  lesions  have  been 
produced  experimentally  in  cattle  by  the  human  type,  and  rare  cases 
of  small,  limited  lesions  due  to  natural  infection  with  this  type  have 
been  found  also  in  this  species.  Cases  of  uterine  infection  of  cattle 
with  avian  tuberculosis  have  been  reported  in  Denmark. 

Tuberculosis  in  poultry  has  been  found'  to  be  caused  by  the  avian 
type  of  tubercle  bacillus  in  100  per  cent  of  all  cases  studied.  Hogs 
contract  tuberculosis  easily  when  fed  on  infected  milk  or  when  run- 
ning in  fields  with  tuberculous  cattle  or  poultry.  The  disease  induced 
in  swine  by  the  bovine  bacillus  is  often  fatal,  but  infection  with  the 
avian  bacillus  very  seldom  becomes  progressive  in  swine,  the  lesions 
being  limited  usually  to  the  lymph  nodes  of  the  head  and  neck. 

Goats  are  experimentally  very  susceptible  to  the  bovine  type  of 
tubercle  bacillus  and,  Avithin  the  past  ten  years,  several  advanced 
cases  of  tuberculosis  in  milch  goats  have  been  observed  by  the  writers 
and  by  others.  Sheep  and  horses  are  more  rarely  affected  with  this 
disease.  The  former  are  susceptible  to  the  bovine  type  and  the  latter, 
while  most  frequently  affected  with  the  bovine  bacillus,  are  also  sus- 
ceptible to  the  other  two  types. 

The  bovine  type  of  bacillus  rarely  causes  the  lung  form  of  the 
disease  in  adult  human  beings,  but  it  is  responsible  for  certain  forms 
of  tuberculosis  in  infancy  and  childhood.  The  percentage  of  cases  of 
bovine  tuberculosis  occurring  among  children  depends  on  local  condi- 
tions, and  is  variously  estimated.  The  cause  of  this  type  of  the  disease 
in  children  is  infection  transmitted  through  raw  milk  and  cream. 


1  Professor  of  Veterinary  Science  and  Veterinarian  in  the  Experiment  Station. 

2  Associate  Professor  of  Veterinary  Science  and  Veterinarian  in  the  Experi- 
ment Station. 


4  CALIFORNIA   AGRICULTURAL   EXTENSION    SERVICE  [CiRC.  21 

It  may  also  be  present  in  other  dairy  products,  such  as  unpasteurized 
butter,  fresh  cheese,  skimmed  milk,  and  buttermilk.  For  this  reason 
the  retailing"  of  unpasteurized  milk  from  cows  that  have  not  passed 
the  tuberculin  test  is  prohibited  by  law  in  California.^ 

THE    ECONOMIC    ASPECT   OF    BOVINE   TUBERCULOSIS 

The  losses  due  to  the  prevalence  of  this  disease  in  farm  animals 
are  not  as  apparent  as  they  are  important.  It  is  no  uncommon  thing 
for  a  veterinarian  to  find  70  or  80  per  cent  of  the  cows  in  a  herd 
tuberculous  without  much  loss  being  evident  to  the  owner.  Losses 
from  deaths  due  to  tuberculosis  seldom  become  serious  in  a  herd  until 
the  disease  has  spread  to  a  majority  of  the  animals.  Often  the  first 
intimation  that  anything  is  wrong  comes  to  the  owner  through  the 
report  from  the  abattoir  that  cattle  from  his  ranch  have  been  con- 
demned as  unfit  for  food  on  account  of  tuberculosis. 

The  proportion  of  hogs  condemned  by  meat  inspectors  on  account 
of  tuberculosis  is  an  indication  of  the  spread  of  infection  in  cattle 
since  the  cow  is  the  chief  source  of  tuberculous  infection  in  swine, 
the  disease  being  transmitted  to  swine  through  milk  or  buttermilk 
from  tuberculous  cows,  through  infected  cattle  corrals  or  by  feeding 
uncooked  carcasses  to  the  hogs.  The  enormous  losses  due  to  this 
disease  are  a  tax  upon  every  pint  of  milk  and  every  pound  of  beef 
sold.  That  the  aggregate  loss  to  the  state  is  enormous  cannot  be 
doubted,  but,  on  the  other  hand,  the  loss  to  the  individual  owner  is 
seldom  so  great  as  to  make  him  ready  to  adopt  measures  involving  a 
great  deal  of  immediate  trouble  and  expense,  in  order  to  secure 
eventual  complete  freedom  from  the  infection. 


3  The  California  Pure  Milk  Law  (Statutes  1927,  Chapter  888)  gives  the  alter- 
native to  either  pasteurize  the  milk  and  cream  sold  at  retail  or  to  submit  the  cattle 
to  an  official  tuberculin  test.  Dairymen  who  sell  in  bulk  to  the  wholesale  trade 
for  pasteurization  need  not  have  their  cows  tested  or  install  a  pasteurizer.  The 
responsibility  of  pasteurization  rests  on  the  creamery.  In  cities  or  counties  having 
an  approved  dairy  inspection  service  all  milk  retailed  must  be  graded  and  properly 
labeled. 

Every  cow  owner  who  intends  to  retail  any  unpasteurized  milk  or  other  dairy 
product,  except  cheese,  should  write  to  The  State  Department  of  Agriculture, 
Sacramento,  California,  requesting  that  his  cows  be  tuberculin  tested.  Those 
intending  to  retail  in  any  city  or  county  having  a  dairy  inspection  service  should 
file  a  duplicate  request  with  the  local  health  officer. 

Pasteurization  on  the  dairy  ranch  is  impracticable  in  most  cases.  Any  dairy- 
man who  is  contemplating  the  installation  of  pasteurization  equipment  is  advised 
to  confer  with  the  officials  of  the  State  Department  of  Agriculture  or  with  the 
chief  dairy  inspector  of  the  city  in  which  his  products  are  used,  for  some  cities 
refuse  to  allow  milk  to  be  sold  unless  it  has  been  pasteurized  within  the  cities. 
It  is,  moreover,  illegal  to  repasteurize  milk  to  be  sold  as  market  milk  for  human 
consumption. 


1928]  BOVINE   TUBERCULOSIS 


THE    SYMPTOMS    OF   TUBERCULOSIS    IN    CATTLE 

There  is  no  symptom  that  can  be  relied  upon  with  certainty.  A 
herd  may  be  badly  infected  and  yet  none  of  the  cattle  show  symptoms 
of  ill  health.  Tuberculosis  may  attack  almost  any  organ  of  the  body, 
but  until  it  has  progressed  to  an  advanced  stage  there  may  be  no 
visible  signs.  Following  are  some  of  the  more  important  symptoms 
suggestive  of  the  disease,  but  it  should  be  understood  that  these  may 
also  be  caused  by  other  diseases : 

Unthriftiness. — In  advanced  stages  of  the  disease  the  coat  may 
become  rough,  the  hair  failing  to  shed  readily  with  the  change  of 
seasons.  The  skin  loses  its  suppleness  and  feels  harsh  and  thick  and 
is  difficult  to  fold  when  grasped  by  the  hands.  This  is  especially 
noticeable  in  the  neck  or  flanks.  This  condition  is  known  as  ''hide- 
bound." The  debilitated  expression  of  the  eyes  and  face,  the  bristling 
hair,  arched  back,  and  tucked-up  abdomen  are  symptoms  which  may 
or  may  not  be  present  in  advanced  tuberculosis. 

Loss  of  Flesh. — A  gradual  falling  away  in  flesh  should  always  be 
a  cause  for  suspicion,  but  leanness  is  a  common  characteristic  of  good 
dairy  cows;  therefore  a  knowledge  of  the  normal  for  each  individual 
animal  is  necessary  before  judgment  may  be  passed  on  this  symptom. 

Cough. — This  symptom  is  only  present  when  the  disease  is  attack- 
ing the  lungs  or  some  part  of  the  breathing  organs.  It  is  usually 
rather  subdued  and  infrequent  and  may  occur  only  when  the  animal 
is  driven  or  when  it  gets  up  after  having  lain  down  for  some  time. 
Tuberculous  cows  do  not  appear  to  expel  anything  when  coughing. 
This  may  be  because  they  cannot  spit.  Most  of  the  material  coughed 
up  from  the  lungs  is  swallowed,  but  many  tuberculosis  germs  escape 
from  the  mouth  in  the  spray. 

Nasal  Discharge. — A  slight  discharge  of  pus  from  the  nostrils  may 
occur  in  cattle  with  advanced  tuberculosis  of  the  lungs.  This  discharge 
is  often  removed  by  the  frequent  licking  of  the  nostrils  and  would 
be  overlooked  by  any  but  a  close  observer. 

Enlarged  Glands. — Hard,  painless  swellings  in  cattle  are  apt  to 
be  due  to  tuberculosis.  These  are  especially  prone  to  occur  in  the 
region  of  the  throat,  in  front  of  the  shoulder,  or  in  the  flank  or  groin. 
Swellings  under  the  jaw  proper  are  more  often  due  to  actinomycosis 
or  to  the  penetration  of  the  tissues  by  foxtail  beards.  Tuberculous 
growths  often  develop  in  the  throat  or  back  of  the  jaws  so  as  to 
produce  a  hoarseness  in  breathing. 


6  CALIFORNIA   AGRICULTURAL    EXTENSION    SERVICE  [ClRC.  21 

Hard  Lumps  in  the  Udder. — When  tuberculosis  attacks  the  udder 
no  change  can  be  detected  at  first,  but  after  a  time  hard  lumps  can 
be  felt  in  some  parts  of  the  organ  after  it  is  milked  out.  Milk  from 
such  an  udder  must  not  be  used. 

Chronic  Bloating.  —  Sometimes  the  diseased  glands  in  the  chest 
prevent  the  usual  passage  of  gas  from  the  paunch  to  the  mouth  by 
pressing  on  the  gullet.  The  resulting  bloat  is  recurrent  or  chronic 
and  easily  distinguishable  from  the  acute  bloating  caused  by  green 
alfalfa. 

Diarrhea.  —  Looseness  of  the  bowels  or  ''scouring"  is  seen  in 
advanced  stages,  particularly  when  the  disease  is  generalized.  This 
kind  of  scouring  does  not  yield  to  treatment. 

WHAT    TUBERCULOSIS    IN    CATTLE    LOOKS    LIKE 

When  the  carcass  of  the  cow  affected  with  tuberculosis  is  opened, 
the  disease  may  be  found  in  any  part  of  the  body,  but  it  is  usually 
located  in  the  lymph  glands  of  the  chest,  throat  or  abdomen.  The 
exteriors  of  the  tubercles  often  look  like  masses  of  piearls,  especially 
when  on  the  chest  or  abdominal  walls,  and  on  this  account  years  ago 
the  disease  was  called  pearl  disease  of  cattle.  Tissues  showing  lesions 
of  tuberculosis  in  cattle  and  hogs  may  be  seen  in  the  veterinary  exhib- 
its of  the  College  of  Agriculture  at  Berkeley.  Colored  plates,  repro- 
ducing the  appearance  of  tuberculous  tissues  in  cattle,  may  be  seen 
in  the  Special  Report  on  Diseases  of  Cattle,  obtainable  for  one  dollar 
from  the  Superintendent  of  Documents,  Washington,  D.  C.  A  limited 
number  of  copies  are  for  free  distribution  by  United  States  Senators 
and  Representatives. 

THE    CAUSE    OF   TUBERCULOSIS    IN    CATTLE 

Although  there  is  much  that  is  yet  to  be  satisfactorily  explained 
concerning  the  way  in  which  cattle  contract  tuberculosis,  it  is  defin- 
itely known  that  the  disease  results  from  the  invasion  of  the  tissues 
of  the   body  by  bacteria.*    The   bacilli   of     bovine  tuberculosis   are 


4  The  Baccillus  tuberculosis  (Kocli)  belongs  to  that  genus  of  microscopic 
plants  known  as  mycobacteria.  When  the  infected  tissue  is  smeared  on  a  glass 
slide  and  properly  stained  the  bacteria  may  be  seen  by  means  of  a  high-power 
microscope  as  slender,  slightly  bent  rods,  .00006  to  .00015  inch  in  length  by 
.00001  to  .00002  inch  in  diameter.  These  organisms  do  not  stain  readily  with 
ordinary  aniline  dyes.  Once  stained  with  carbobfuchsin,  however,  the  dye  is 
retained  even  after  the  application  of  alcoliol  or  80  per  cent  sulphuric  or  hydro- 
chloric acid.  For  this  reason  tubercle  bacilli  and  a  few  other  species  of  bacteria 
are  classed  as  ''acid  and  alcohol  fast^',  as  distinguished  from  those  which  lose 


1928]  BOVINE   TUBERCULOSIS  7 

believed  to  exist  only  in  the  tissues  of  diseased  animals  and  in  their 
excretions,  or  on  substances  contaminated  by  these  excretions.  Except 
under  the  most  favorable  conditions  they  do  not  multiply  outside  the 
body,  although  if  not  killed  by  sunlight  or  disinfectants  they  may 
survive  in  moist  dirt  for  several  months. 

Tuberculosis  in  cattle  and  swine  is  not  hereditary.  A  few  cases 
are  recorded  where  animals  have  been  born  tuberculous,  but  only 
when  the  reproductive  organs  of  the  mother  were  diseased. 

HOW   THE    DISEASE    SPREADS 

When  an  animal  first  becomes  infected  there  is  usually  no  danger 
to  other  animals,  but  sooner  or  later  tuberculous  cattle  may  begin 
to  have  infectious  discharges.  The  germs  escaj^e  through  the  mouth 
and  nose,  the  bowels,  the  milk,  with  discharges  from  the  genital 
organs  and  from  open  lesions  in  any  part  of  the  body.  When  the 
disease  is  located  in  the  lungs  and  discharges  into  the  air  tubes,  pieces 
of  diseased  tissue  and  millions  of  germs  are  liberated  and  coughed 
up.  Most  of  these  are  swallowed  and  passed  out  in  the  manure.  This 
is  the  chief  way  in  which  the  tubercle  bacilli  are  discharged  from 
diseased  cattle.  When  the  germs  are  being  given  off  in  any  of  these 
ways,  the  disease  is  known  as  open  tuberculosis.  Cattle  in  advanced 
stages  of  the  disease  usually  have  open  tuberculosis.  The  high  per- 
centage of  tuberculous  cattle  and  hogs  on  certain  ranches  has  been 
found  to  be  due  to  the  failure  of  the  owners  to  remove  promptly 
animals  that  develop  visible  indications  of  the  disease. 

Tubercle  bacilli  discharged  from  the  mouth  and  nose  are  coughed 
up  from  the  lungs  and  are  sprayed  over  the  food  in  front  of  the  cow 
or  are  carried  in  the  air  for  a  time  until  they  fall  to  the  ground. 
Cows  in  adjoining  stalls  may  take  in  these  germs  in  the  air  they 
breath  or  in  the  food  they  eat,  and  so  contract  the  disease. 

Germs  discharged  from  the  bowels  are  mixed  with  the  manure 
and  may  infect  cattle  and  hogs  that  are  allowed  to  pick  over  the  dung 


the  color  of  their  stain  when  treated  with  alcohol  and  acid.  Tubercle  bacilli  are 
not  readily  obtained  in  pure  culture  from  tuberculous  tissues.  The  usual  method 
is  to  inoculate  guinea  pigs  and  from  their  diseased  tissues  inoculate  a  large 
number  of  tubes  containing  egg  media.  When  once  started  to  grow  on  egg  media 
the  germs  can  be  transferred  and  more  readily  cultivated  on  glycerine  bouillon. 
Tubercle  bacilli  of  cattle,  man  and  birds  may  be  distinguished  from  one 
another  by  appropriate  laboratory  methods.  The  human  and  bovine  types  are  both 
fatal  for  guinea  pigs.  The  human  variety  is  only  mildly  pathogenic  for  rabbits 
or  cattle  and  the  tissue  changes  which  it  produces  in  these  are  slight  and  usually 
restricted  to  the  point  of  inoculation.  Tlie  bovine  variety  wlien  inoculated  into 
cattle  or  rabbits  is  fatal  as  a  rule. 


8  CALIFORNIA   AGRICULTURAL    EXTENSION    SERVICE  [ClltC.  21 

heap.  The  practice  of  having  hogs  and  cattle  together  in  the  same 
yard  often  results  in  the  infection  of  the  hogs,  if  any  of  the  cattle 
are  affected.  Manure  containing  tuberculosis  germs  may  easily  infect 
the  milk.  Particles  of  manure  may  fall  into  the  milk  pail  from  the 
skin  of  a  dirty  cow  or  be  accidentally  flicked  off  the  tail  and  fall  into 
the  milk.  Straining  the  milk  afterwards  removes  only  the  larger 
particles.  The  smaller  ones,  including  the  germs  of  the  disease,  remain 
in  the  milk.  When  the  udder  is  tuberculous,  the  milk  contains  the 
germs  in  vast  numbers.  Although  such  milk  may  look  and  taste 
perfectly  good,  it  may  transmit  the  disease.  Hogs  and  calves  are 
readily  infected  by  it.     It  is  also  dangerous  to  children. 

When  all  the  tuberculous  areas  in  the  body  are  so  situated  that 
no  tubercle  bacilli  are  being  given  off  or  discharged  in  the  secretions, 
as  above  described,  the  condition  is  known  as  closed  tuberculosis. 
Such  animals  do  not  transmit  the  infection  until  they  become  so 
diseased  that  the  tuberculous  areas  open  into  a  passage  leading  to  the 
exterior  of  the  body.  Many  infected  cattle  never  develop  open  tuber- 
culosis, but  there  is  no  way  of  determining  accurately  in  living  cattle 
which  are  the  open  cases  and  which  are  closed.  In  badly  infected 
herds  a  careful  physical  examination  by  a  veterinarian  will  eliminate 
a  certain  proportion  and  a  much  larger  proportion  may  be  detected 
by  the  inoculation  of  guinea  pigs.  This  latter  procedure,  however,  is 
impracticable  under  average  dairy  conditions  and  it  will  fail  to  detect 
those  cases  which  do  not  happen  to  discharge  germs  at  the  exact  time 
the  sample  is  taken. 

Bate  of  Development. — Individual  animals  exhibit  the  widest 
variation  in  the  duration  of  the  disease.  In  the  majority  the  disease 
pursues  a  leisurely  course,  consuming  years  before  causing  death. 
Most  infected  cattle  are  fattened  and  sold  for  beef,  but  some  develop 
a  rapidly  fatal  type.  Its  onset  is  always  unobtrusive  and  its  progress 
is  so  gradual  that  its  presence  does  not  cause  apprehension.  Losses 
are  so  evenly  distributed  in  point  of  time  that  they  do  not  excite 
serious  alarm,  as  do  other  less  destructive  diseases  of  the  pestilential 
type  which  kill  many  suddenly.  The  rate  of  spread  in  a  herd  is  vari- 
able. In  some  herds  which  are  known  to  have  a  few  reacting  animals 
the  disease  does  not  seem  to  spread.  Perhaps  this  is  due  to  the  fact 
that  few,  if  any,  of  these  happen  to  be  open  cases.  On  the  other  hand, 
in  certain  instances  under  observation  the  disease  has  been  introduced 
into  clean  herds  and  in  a  few  months,  through  the  development  of 
open  cases,  a  large  proportion  of  the  cattle  have  become  reactors.  The 
feeding  of  infected  milk  to  calves,  particularly  unheated  mixed  skim- 
milk  returned  from  the  creamery,  usually  results  in  speedy  infection. 


1928]  BOVINE   TUBERCULOSIS 


HOW   A    HERD    IS    INFECTED 

Tuberculosis  may  be  introduced  into  a  healthy  herd  in  a  number 
of  ways : 

1.  By  the  purchase  of  a  bull  or  other  animal  that  is  infected  with 
the  disease.  This  animal  may  be  apparently  healthy  at  the  time  of 
purchase,  but  if  previously  exposed  the  disease  may  develop  and  be 
spread  to  other  cattle.  Where  a  healthy  herd  is  being  maintained, 
animals  should  only  be  bought  subject  to  the  tuberculin  test  and  even 
this  precaution  may  fail  if  the  herd  from  which  they  come  is  infected. 

2.  By  feeding  calves  with  milk,  buttermilk,  or  whey  that  has  come 
from  tuberculous  cows.^  A  farmer  may  have  a  healthy  herd,  but,  if 
he  brings  home  skim-milk  from  a  creamery  and  feeds  it  to  his  calves, 
the  germs,  if  present  in  the  milk,  may  be  transmitted  to  them.  Such 
milk  should  be  rendered  safe  by  boiling  or  pasteurizing. 

3.  By  showing  cattle  at  fairs  and  exhibitions  where  proper  care 
is  not  taken  to  keep  out  diseased  stock,  or  to  disinfect  the  stables. 

4.  By  shipping  animals  in  cars  that  have  not  been  disinfected,  as 
these  may  have  recently  carried  diseased  cattle. 

5.  By  allowing  the  cattle  to  graze  with  diseased  ones,  or  to  come 
into  contact  with  them  over  fences. 

6.  When  the  cattle  are  permitted  access  to  small  ponds,  water 
holes,  or  troughs,  these  may  become  badly  contaminated  with  infec- 
tion from  "open  cases".  The  rapid  spread  of  the  disease  on  certain 
ranges  is  believed  to  be  due  in  part  to  infected  water. 

7.  Improperly  sterilized  bone  meal  used  in  certain  cattle  feeds  or 
so-called  mineral  mixtures  has  been  suggested  by  some  to  have  occa- 
sionallv  transmitted  tuberculosis. 


HOW  THE   PRESENCE   OF   TUBERCULOSIS    INFECTION    MAY    BE 

DEMONSTRATED 

The  tuberculin  reaction  is  the  best  method  at  j^resent  available 
for  the  recognition  of  tuberculous  infection  in  cattle.  There  are 
several  reasons  why  this  special  test  is  necessary.  Unless  cattle  are 
badly  diseased  they  seldom  show  symptoms  of  ill  health.  Almost  any 
organ  of  the  body  may  be  attacked,  but  until  the  abnormal  process 
has  progressed  far  enough  to  interfere  seriously  with  some  function, 
no  symptoms  can  be  detected.  The  thickness  of  the  skin  and  chest 
wall  makes  it  difficult  to  detect  a  diseased  condition  in  a  cow's  lung 


5  California  Statutes  1921,  Chapter  696  requires  creameries  to  pasteurize  skim 
milk  and  other  by-products  returned  to  farms  for  feeding. 


10  CALIFORNIA   AGRICULTURAL   EXTENSION   SERVICE  [ClRC.  21 

by  listening  to  the  sounds  made  in  breathing,  whereas  this  is  com- 
paratively easy  in  human  beings.  Next  to  the  tuberculin  test,  a 
careful  physical  examination  by  a  trained  veterinarian  is  the  most 
practicable  method  of  diagnosis ;  in  fact,  the  tuberculin  test  should 
always  be  supplemented  by  such  an  examination,  since  badly  diseased 
cattle  often  do  not  react  to  the  test. 

Other  methods  which  occasionally  may  be  useful  in  detecting  the 
disease  are  the  microscopic  examination  or  the  guinea-pig  inoculation 
of  diseased  tissue,  exudates  from  the  pulmonary,  intestinal  or  urinary 
tracts  and  pus  from  abscesses.  Animal  inoculation  with  such  material 
is  a  much  more  certain  test  than  a  direct  microscopic  examination. 

TUBERCULIN    AND    ITS    USES 

Tuberculin  is  the  filtered  and  sterilized  glycerine  bouillon  upon 
which  tubercle  bacilli  have  grown.  It  contains  no  germs  and  is  harm- 
less to  healthy  cattle  even  in  increased  dosage.  All  tuberculin  entering 
into  interstate  trade  must  be  produced  in  a  laboratory  under  U.  S. 
government  inspection.  Each  bottle  must  indicate  on  its  label  the 
equivalent  strength  in  terms  of  Koch's  old  tuberculin.  When  the 
tuberculin  is  concentrated  to  1/lOth  of  the  volume  of  the  original 
inoculated  glycerine  bouillon,  it  is  known  as  Koch's  O.T.  or  old  tuber- 
culin. In  tuberculous  cattle  it  produces  a  temporary  effect  or  reaction. 
The  living  tissues  of  tuberculous  persons  and  animals  are  hypersen- 
sitive to  tuberculin.  This  sensitiveness  is  most  marked  in  the  tissues 
that  are  actually  invaded  by  the  germs,  but  it  also  exists  to  some 
extent  in  the  other  tissues  of  the  body  which  contain  blood  vessels. 
The  living  tissues  of  individuals  not  infected  with  tuberculosis  show 
no  sensitiveness  to  tuberculin. 

When  tuberculin  is  injected  into  the  vascular  layers  of  the  skin 
of  a  tuberculous  cow,  a  swelling  will  usually  follow.  When  dropped 
on  the  eyeball,  an  exudate  of  pus  may  result.  When  injected  under 
the  skin  in  sufficient  amount,  a  general  systemic  response  occurs 
which  is  chiefly  manifested  by  a  rise  in  temperature,  usually  between 
the  eighth  and  the  twentieth  hour  after  the  tuberculin  is  adminis- 
tered, lasts  a  few  hours  and  then  subsides.  These  symptoms  are 
called  reactions,  and  animals  which  show  them  are  called  reactors. 
The  value  of  the  test  lies  in  the  fact  that  a  high  percentage  of  tuber- 
culous animals  react,  while  healthy  ones  do  not. 

There  are  several  ways  of  testing  with  tuberculin.  The  methods 
which  are  most  practicable  are  the  intradermie,  the  subcutaneous  and 
the  ophthalmic.    Each  of  these  methods  has  certain  advantages.    The 


1928]  BOVINE   TUBERCULOSIS  11 

conditions  under  which  the  testing  is  to  be  performed  should  be  the 
guide  in  choosing  the  method.  The  properly  combined  use  of  all 
three  tests  on  the  same  animals  gives  the  highest  accuracy  in  diagnosis. 
Training  and  experience  are  necessary  for  a  veterinarian  to  secure 
best  results.   In  brief  the  procedure  is  as  follows : 

(a)  The  intradermic  test  consists  of  injecting  two  or  three  drops 
of  tuberculin  into  the  layers  of  the  skin.  The  location  usually  pre- 
ferred by  veterinarians  is  one  of  the  folds  of  skin  on  the  under  side 
of  the  base  of  the  tail.  A  positive  intradermic  reaction  is  indicated 
by  a  thickening  of  the  fold.  This  thickening  is  usually  best  observed 
between  48  and  120  hours  after  injection. 

{!))  The  subcutaneous  test  consists  in  injecting  two  to  four  cubic 
centimeters  of  diluted  tuberculin  beneath  the  skin  of  the  neck  or 
shoulder.  The  reaction  consists  in  a  rise  of  temperature  between  8 
and  20  hours  after  injection,  and  occasionally  by  symptoms  of  depres- 
sion, shivering,  bristling  hair,  ceased  rumination,  and  looseness  of 
the  bowels. 

(c)  The  opthalmic  test  consists  in  placing  under  the  eyelid  a 
small  disc  of  milk  sugar  permeated  with  tuberculin,  or  applying  the 
concentrated  fluid  form  to  the  eyeball.  The  best  results  are  obtained 
by  the  sensitized  test.  This  consists  of  two  instillations,  two  to  three 
days  apart.  The  reaction  consists  in  a  mild  inflammation  of  the  eye 
with  a  discharge  of  pus,  which  usually  ceases  in  a  few  hours. 


LIMITATIONS   OF   THE   VARIOUS    METHODS    OF   TESTING 

No  form  of  the  tuberculin  test  destinguishes  between  severe  and 
slight  cases,  nor  between  those  that  are  spreading  infection  and  those 
that  are  not  inconvenienced  by  the  disease  and  are  not  infecting 
others.  The  test  is  searching  and  even  in  an  extremely  slight  infection 
will  cause  the  animal  to  react.  In  cattle  reacting  to  the  test  the 
infection  may  occasionally  be  so  recent  and  the  changes  so  slight  that 
the  ordinary  methods  of  postmortem  examination  fail  to  demonstrate 
the  presence  of  tuberculosis,  since  the  lesions  may  be  microscopic  in 
size.  If  no  reaction  occurs,  care  must  be  taken  for  there  is  still  a 
chance  that  the  disease  is  present.  Each  form  of  the  test  has  its  special 
value  and  limitations.  Nevertheless,  the  tuberculin  test  is  the  most 
accurate  and  valuable  means  at  hand  for  the  diagnosis  of  tuberculosis 
in  cattle.    Following  are  some  of  the  factors  to  be  considered : 

(1)  The  animal  may  not  react  if  very  extensive  tuberculous, 
but  in  such  cases  physical  symptoms  will  usually  indicate  ill  health. 


12  CALIFORNIA   AGRICULTURAL   EXTENSION    SERVICE  [CiRC.  21 

(2)  The  reaction  does  not  occur  during  the  period  of  incubation 
of  the  disease;  in  infected  herds  a  second  test  should,  therefore,  be 
made  in  from  sixty  to  ninety  days. 

(3)  Cows  that  have  once  reacted  may  fail  to  do  so  upon  subse- 
quent tests,  but  frequently,  in  such  cases,  the  disease  is  known  to 
have  become  active  again  after  a  time. 

(4)  The  possibility  of  the  cattle  having  been  ''plugged"  (ren- 
dered insensitive)  by  the  previous  injection  of  tuberculin  must  be 
taken  into  account.  The  discovery  that  the  ophthalmic  test  will 
usually  cause  reactions  in  ' '  plugged ' '  tuberculous  cattle  has  somewhat 
decreased  the  importance  of  the  chance  of  error. 

(5)  Sometimes  tuberculous  animals  have  been  observed  to  react 
to  one  form  of  test  and  fail  to  respond  to  the  others.  A  proportion 
of  such  cases  may  be  due  to  lack  of  sufficient  care  to  observe  the  effects 
of  the  tuberculin  upon  the  individual,  i.e.,  failure  in  the  subcutaneous 
test  to  take  sufficient  temperatures;  failure  in  the  intradermic  test 
to  inspect  the  point  of  injection  at  proper  intervals;  failure  in  the 
ophthalmic  test  to  keep  the  animals  under  proper  environment  and 
constant  observation. 


CHRONIC    LYMPHANGITIS    A    CONFUSING    FACTOR 

Cattle  are  sometimes  affected  with  nodular  lesions  of  the  skin  and 
subcutaneous  tissues  in  which  avirulent,  acid-fast  bacilli,  resem- 
bling Bacillus  tuberculosis,  are  present.  This  condition  is  sometimes 
called  skin  tuberculosis.  Crawford^  has  suggested  the  term  "subcuta- 
neous tubercular  nodule ' ' ;  subcutaneous,  because  the  lesions  are  under 
the  skin ;  tubercular  in  preference  to  tuberculous  since  the  latter  term 
pertains  more  strictly  to  lesions  caused  by  virulent  tubercle  bacilli. 
The  choice  of  names  for  these  conditions  should  not  be  made  until  the 
nature  of  the  various  acid-fast  organisms  found  in  these  nodules  is 
more  satisfactorily  established.  The  nodules  are  visible  in  the  living 
animal,  but  may  be  so  small  that  they  do  not  attract  attention.  They 
do  not  spread  to  the  viscera  or  internal  lymphatics  or  interfere  in  any 
way  with  the  efficiency  of  the  animal.  The  presence  of  these  nodules 
may  render  an  animal  sensitive  to  tuberculin.  The  condition  has  been 
found  in  herds  that  are  free  from  virulent  tuberculosis  and  it  is  some- 
times impossible  for  a  veterinarian,  when  tuberculin  testing  a  herd 
where  this  disease  is  present,  to  certify  that  the  herd  is  free  from 


6  Crawford,  A.  B.    Studies  in  so-called  ''skin  lesion"  tuberculosis.    Jour.  Amer, 
Vet.  Assn.,  73:216-222.    1928. 


1928]  BOVINE   TUBERCULOSIS  13 

reactors  although  he  may  believe  that  there  are  no  cattle  present  which 
harbor  virulent  tubercle  bacilli.  Extensive  experiments  at  this  Station 
by  Traum^  have  thus  far  failed  to  show  that  the  bacilli  in  these  nodules 
develop  into  virulent  organisms  or  induce  lesions  in  the  experimental 
animals  such  as  tubercle  bacilli  do. 

RE-TESTS    OF    REACTORS    NOT    PERMITTED 

One  reaction  to  the  tuberculin  test  is  considered  evidence  that  an 
animal  is  tuberculous.  Nothing  can  be  accomplished  by  a  re-test 
except  possible  confusion  in  the  mind  of  the  owner,  as  an  animal  that 
has  once  reacted  may  not  react  to  a  subsequent  test ;  but,  at  the  same 
time,  it  may  become  a  dangerous  spreader  of  tuberculosis.  Once  a 
reactor,  always  tuberculous  is  the  only  safe  motto  in  this  respect.  The 
state  and  federal  authorities  do  not  allow  official  re-tests  on  animals 
that  are  known  to  have  positively  reacted  to  tuberculin. 

DISPOSING    OF    REACTING    CATTLE 

The  California  law^  requires  that  cattle  which  react  positively  to 
the  tuberculin  test  be  branded  on  the  left  jaw  with  the  letter  T.  In 
lieu  of  branding  pure-bred  cattle,  the  registry  name  and  number  and 
photographs  may  be  filed  at  the  office  of  the  State  Department  of 
Agriculture,  Sacramento.  Only  an  approved  licensed  or  official  veter- 
inarian may  legally  test  cattle  with  tuberculin  in  California,  and  he 
must  report  the  results  of  all  tests  to  the  State  Department  of  Agri- 
culture, Sacramento.  That  office  has  supervision  over  the  disposition 
of  tuberculin  to  be  used  on  animals  in  this  state. 

The  retention  of  reacting  branded  cattle  in  herds,  the  milk  from 
ivhich  is  pasteurized,  is  a  procedure  sometimes  resorted  to  instead  of 
their  slaughter  for  beef.  Under  special  conditions  it  is  also  permis- 
sible to  sell  known  tuberculous  cattle  to  be  placed  in  infected  herds. 
The  retention  of  reacting  cattle  in  herds  from  which  milk  or  milk 
products  are  being  used  in  a  raw  or  unpasteurized  condition  is  illegal 
in  California. 

Slaughter  for  beef  under  inspection  is  the  recommended  method 
for  disposal  of  most  reacting  cattle  which  show  no  visible  signs  of 
the  disease,  except  in  those  cases  where  the  beef  value  would  be  very 
much  less  than  the  dairy  or  breeding  value.    The  method  formerly 


7  Traum,   J.    Lymphangitis   in   cattle   caused   by   acid-fast   organism.     Cornell 
Veterinarian  13:240-245.    1923 

8  Statutes  of  California,  1927,  chapter  47. 


14  CALIFORNIA   AGRICULTURAL    EXTENSION    SERVICE  [CiRC.  21 

and  most  commonly  employed  of  disposing  of  reacting  animals  was 
by  slaughter  and  burial.  Where  this  wasteful  method  has  been 
employed  the  results  have  been  discouraging;  even  when  the  state 
recompensed  the  owner  in  part  for  the  loss  of  his  stock,  it  has  been 
unsatisfactory  and  is  now  seldom  practised.  A  large  proportion  of 
reacting  animals  are  usually  only  slightly  diseased.  They  readily  take 
on  flesh  and  can  be  fattened  and  used  for  beef.  The  University  prac- 
tices what  it  preaches  in  this  regard,  in  that  reacting  cows  are  sold 
for  food  purposes  under  official  municipal,  state  or  federal  inspection. 
In  every  case,  cattle  must-  be  carefully  examined  by  an  official 
inspector  when  killed  and  if  the  disease  is  found  to  be  extensive,  the 
carcass  must  be  condemned.  The  federal  government  meat  inspection 
regulations  admit  the  use  for  food  of  meat  from  animals  that  show 
limited  lesions  of  tuberculosis  in  the  non-edible  viscera,  for  it  is 
recognized  that  the  meat,  itself,  does  not  contain  tubercle  bacilli  and, 
besides,  the  common  procedure  of  cooking  meat  is  a  further  safeguard 
against  danger.  The  disposition  of  reacting  cattle  depends  upon 
various  conditions;  these  are  more  fully  discussed  later  in  this 
circular. 

FACTORS    IN    THE    CONTROL   OF    BOVINE    TUBERCULOSIS 

In  the  application  of  any  methods  for  the  eradication  or  preven- 
tion of  tuberculosis  certain  important  characteristics  of  the  disease 
should  be  borne  in  mind : 

(1)  Its  indigenous  nature.  Bovine  tuberculosis  is  so  firmly  rooted 
and  so  widespread  among  dairy  cattle  that  it  is  exceptional  for  an 
important  dairy  community  to  be  free  from  it.  The  possibility  of 
eradicating  bovine  tuberculosis  from  individual  herds  and  from 
certain  entire  counties  has  been  demonstrated  beyond  all  question, 
and  the  obstacles  which  have  prevented  the  successful  accomplish- 
ment of  this  in  states,  or  countries  have  been  due  to  the  unwillingness 
of  the  people  to  make  the  necessary  financial  sacrifices. 

(2)  Its  specific  nature.  Tuberculosis  does  not  develop  sponta- 
neously. The  cause  of  the  disease  is  the  bacillus  of  tuberculosis  which 
exists  only  in  the  bodies  of  tuberculous  animals  and  in  their  secretions, 
or  in  substances  contaminated  by  them.  In-and-in  breeding  cannot 
produce  it.  Dark,  filthy,  badly  ventilated  stables,  poor  food  and 
crowded  conditions  may  contribute  to  its  rapid  spread  among  cattle, 
but  the  disease  does  not  originate  in  an  animal,  no  matter  how  bad  its 
environment.  It  must  be  exposed  to  the  disease  germs  to  contract  the 
disease. 


1928]  BOVINE   TUBERCULOSIS  15 

(3)  Its  infectious  nature.  Tuberculosis  is  easily  transmitted. 
This  point,  in  connection  with  its  specific  nature,  cannot  be  too 
strongly  emphasized.  The  disease  results  from  the  association  of 
tuberculous  cattle  with  healthy  ones  and  under  such  conditions  will 
spread  in  spite  of  every  sanitary  precaution.  It  is  a  mistake  to  assume 
that  the  disease  cannot  thrive  and  multiply  among  dairy  cattle  kept 
under  ideal  conditions.  The  invigorating  influence  of  fresh  air  and 
sunshine,  wide,  well  watered  pastures,  well  ventilated,  ideally  con- 
structed, immaculately  clean  barns,  and  abundant  and  well  balanced 
rations  will  not  stop,  although  they  are  likely  to  retard,  the  spread 
of  the  disease.  It  is  among  some  of  the  best  kept  herds  that  the 
disease  has  been  found  to  be  alarmingly  prevalent.  Contact,  direct 
or  indirect,  is  the  chief  way  in  which  the  disease  is  disseminated. 
Calves  most  frequently  contract  the  disease  from  the  milk.  Calves 
and  hogs  fed  on  unpasteurized  milk  from  tuberculous  cows  soon 
become  infected. 


SUPPRESSION    OF    THE    DISEASE    BY    THE    COW    OWNERS 

The  first  step  in  getting  rid  of  the  disease  is  to  find  out  how  many 
of  the  herd  are  affected.  A  veterinarian  should  apply  a  tuberculin 
test  and  make  a  careful  physical  examination  of  each  animal.  The 
proper  course  to  j^ursue  then  will  depend  largely  upon  the  propor- 
tion of  reactors  found. 

The  Suppression  of  Tuherculosis  in  Slightly  Infected  Herds. — 
Suppose  a  few  cattle  react,  say,  less  than  15  per  cent.  Individual 
owners  of  such  herds  are  advised  to  start  to  exterminate  the  disease 
immediately.    The  steps  necessary  are : 

1.  Dispose  of  all  the  reactors,  including  cattle  which  may  have 
given  doubtful  or  questionable  reactions.  Non-reactors  which  on 
physical  examination  show  any  symptoms  attributable  to  tuberculosis 
must  be  included. 

2.  Thoroughly  clean  and  disinfect  the  premises.^  Since  chemical 
disinfectants  in  dilutions  practicable  for  the  liberal  use  required  in 
disinfecting  stables  and  corrals  act  very  slowly  in  killing  tubercle 
bacilli  in  exudate  and  secretions,  most  dependence  should  be  placed 
on  thorough  cleaning,  painting,  and  whitewashing.  Particular  atten- 
tion should  be  given  to  the  absolute  removal  of  all  damp  manure, 
the  smallest  particles  of  which  may  harbor  innumerable  tuberculosis 


9  For  a  description  of  methods  of  stable  disinfection,  write  to  the  Office  of 
Information,  United  States  Dei^artnient  of  Agriculture,  Washington,  D.  C,  for 
Farmers'  Bulletin  954. 


16  CALIFORNIA   AGRICULTURAL   EXTENSION   SERVICE  [Cmc.  21 

germs.  In  perfectly  dry  manure  or  soil,  the  tubercle  bacillus  dies  in 
a  few  weeks,  but  under  moist  conditions  it  has  been  found  to  live  for 
over  a  year. 

3.  Re-test  the  herd  in  sixty  or  ninety  days  by  applying  the  intra- 
dermic  or  subcutaneous  combined  with  the  sensitized  ophthalmic 
method,  immediately  remove  all  reactors  and  again  clean  and  disin- 
fect. Every  six  months  make  a  tuberculin  test.  Even  when  the  herd 
is  believed  to  be  free  from  reactors,  annual  testing  is  recommended. 

4.  Additions  to  the  herd  should  be  subjected  to  the  tuberculin 
test  and  should  come  from  herds  that  are  free  from  reactors.  When 
purchasing  cattle  it  is  often  impossible  to  find  any  for  sale  from  herds 
known  to  be  free  from  tuberculosis.  Under  such  conditions,  they 
should  be  obtained  from  herds  in  which  the  percentage  of  reactors  is 
low.  The  purchase  of  cattle  from  badly  infected  herds,  even  when 
they  pass  the  tuberculin  test,  is  dangerous.  There  is  great  danger 
in  buying  non-reacting  cattle  from  infected  herds — that  is,  animals 
that  have  been  exposed  to  infection.  The  unit  to  deal  with  in  buying 
cattle  is  the  sound  herd  rather  than  the  non-reacting  individual  animal. 

In  the  dairies  near  cities,  where  it  is  not  economical  to  raise  the 
calves  and  the  milking  herd  is  kept  up  by  the  constant  purchase  of 
'^springers,"  or  fresh  cows,  it  will  be  impossible  to  keep  the  herd  free 
from  reactors,  although  in  certain  dairies  of  this  class  the  number 
of  reactors  is  kept  down  to  an  average  of  about  3  per  cent  by  semi- 
annual testing  and  the  prompt  removal  of  reactors. 

The  Suppression  of  Tuberculosis  in  Moderately  Infected  Herds. — 
In  herds  having  from  15  to  35  per  cent  of  reactors  the  best  course 
to  pursue  is  not  as  definitely  known  as  in  badly  infected  herds  or  in 
slightly  infected  ones.  The  system  advocated  some  years  ago  of  trying 
to  retain  under  isolated  conditions  a  group  of  reactors  in  order  to 
secure  healthy  calves  from  them  is  practicable  only  when  entirely 
separate  barns,  fields,  and  equipment  are  available;  that  means,  in 
fact,  the  maintenance  of  two  separate  farms. 

In  badly  infected  herds,  one  should  proceed  as  if  every  animal  were 
infected.  In  herds  having  over  35  per  cent  of  reactors  all  of  the 
mature  cattle  should  be  treated  as  if  infected.  The  tuberculin  test  is 
of  value  in  indicating  that  a  severe  infection  exists,  but  not  of  value 
in  such  herds  as  a  means  of  dividing  the  non-infected  from  the  tuber- 
culous animals.  To  control  the  disease  dependence  must  be  placed 
upon  the  following  procedure : 

1.  Eliminate  promptly  all  animals  developing  physical  signs  of 
the  disease. 


1928]  BOVINE   TUBERCULOSIS  17 

2.  Eemove  all  calves  at  birth  and  raise  them  on  boiled  or  pasteur- 
ized milk,  or  a  solution  of  dry  skim  milk. 

3.  Keep  all  healthy  young"  stock  isolated  from  the  infected  herd 
and  infected  fields  and  water.  Test  them  every  six  months  by  the 
intradermic  method  and  remove  any  reactors.^^ 

Calves  are  so  seldom  born  tuberculous  that  intrauterine  trans- 
mission is  not  an  important  factor  in  the  control  of  the  disease. 
Further,  when  calves  do  become  infected,  they  react  satisfactorily 
to  the  intradermic  tuberculin  test  and  seldom  develop  into  spreaders 
until  maturity;  hence,  it  would  require  only  one  generation  of  cattle 
to  eradicate  tuberculosis.  In  carrying  this  principle  into  effect  the 
ideal  way  would  be  to  build  up  a  separate  herd  from  the  healthy 
young  stock. 

BCG    VACCINE 

A.  Calmette,  of  the  Pasteur  Institute,  Paris,  and  C.  Guerin,  of  the 
Pasteur  Institute,  Lille,  France,  observed  a  culture  of  bovine  tubercle 
bacilli,  grown  on  glycerine-bile-potato,  which  became  reduced  in  viru- 
lence so  that  no  injury  resulted  when  50  to  100  milligrams  of  such 
g-rowth  were  injected  under  the  skin  of  the  dewlap  of  calves.  They 
claim  that  calves  may  be  resistant  to  tuberculous  infection  in  this 
way,  and  have  named  the  vaccine  BCG  (bile-treated  bacilli  of  Cal- 
mette and  Guerin). 

Trials  on  calves  are  being  made  in  several  European  countries, 
also  in  the  experimental  herd  of  the  California  Agricultural  Experi- 
ment Station.  No  injury  appears  to  have  resulted  from  the  injection 
of  young  calves  or  the  annual  re-injection  of  heifers.  The  atten- 
uated bacilli,  however,  remain  alive  in  the  tissues  at  the  point  of 
injection  for  a  long  time,  and  although  no  spread  or  reactivation  has 
thus  far  been  noted,  it  is  not  yet  known  what  the  effect  will  be  on 
cows  subjected  to  the  strain  of  pregnancy  and  prolonged  lactation.  It 
will  also  require  several  years  to  determine  the  degree  of  resistance 
to  tuberculosis  conferred  by  BCG.  Results  at  the  California  Station 
indicate  that  this  vaccine  can  have  only  a  very  limited  field  of  use- 
fulness in  the  eradication  of  tuberculosis  in  farm  animals  under 
conditions  as  they  now  exist  in  the  United  States. 


10  Even  when  the  non-reacting  cattle  are  at  once  removed  from  a  herd  having 
over  35  per  cent  reactors,  they  should  be  looked  upon  as  suspicious. 


18  CALIFORNIA   AGRICULTURAL   EXTENSION    SERVICE  [CiRC.  21 


THE   IMPORTANCE  OF  SEGREGATION   AND    ISOLATION 

In  large  herds  it  is  advisable  to  keex3  the  cattle  in  small  units. 
In  constructing  buildings  and  corrals,  plan  at  the  least  to  have 
separate  corrals  for  each  group  of  fifty  or  sixty  cattle.  Provide 
separate  watering-troughs  for  each  corral.  Train  the  cows  to  stand 
always  in  the  same  stanchion.  Do  not  feed  the  calves  with  the  sweep- 
ings from  the  feeding-troughs  in  the  dairy  barn  and  do  not  permit 
hogs  or  goats  in  the  cattle  corrals. 

MAKING   CATTLE   ENVIRONS   FREE    FROM    INFECTIVE 
TUBERCULOUS    MATERIAL 

In  four  series  of  experiments,  Traum^^  found  that  tubercle  bacilli 
contained  in  the  discharges  of  tuberculous  cattle  when  exposed  on  the 
ground  in  a  layer  of  manure  from  one-half  to  one  inch  in  thickness 
failed  to  produce  tuberculosis  in  guinea  pigs  and  cattle  soon  after  the 
medium  in  which  they  were  contained  was  sensibly  dry.  In  one  such 
series,  this  occurred  seventeen  days  after  manure  containing  tubercle 
bacilli  was  placed  on  the  ground.  In  the  case  of  tubercle  bacilli  con- 
tained in  manure  as  above  but  kept  continuously  moist,  as  in  a  water- 
hole,  they  were  found  to  be  capable  of  producing  tuberculosis  in  guinea 
pigs  687  days  after  exposure  in  one  series  and  548  days  after  exposure 
in  another. 

To  date,  it  has  been  found  that  such  tuberculous  material,  when 
mixed  with  manure  and  kept  moist  for  255  days,  produced  tuberculosis 
in  three  out  of  five  cattle  when  placed  in  their  drinking  water. 
Eighteen  out  of  twenty-one  cattle  similarly  exposed  earlier  in  the 
experiment  also  developed  tuberculosis.  After  255  days,  recognizable 
infected  material  was  no  longer  found,  and  cattle  exposures  in  this 
series  were  discontinued. 

SUGGESTIONS    REGARDING    SANITATION 

Construct  water  troughs  so  that  the  drinking  water  of  the  cattle 
does  not  become  contaminated  wdth  manure.  Do  not  allow  the  cattle 
access  to  ponds  or  water  holes.  Have  plenty  of  windows  to  admit  an 
abundance  of  sunlight  to  all  buildings.  Direct  sunlight  is  more  deadly 
to  fully  exposed  tubercle  bacilli  than  carbolic  acid,  cresol,  corrosive 
sublimate  or  chloride  of  lime  in  the  dilutions  general  used  in  disin- 
fecting. 


11  Traum,  J.  Making  cattle  environs  free  from  infection  eliminated  by  tuber- 
culous cattle.  Jour.  Amer.  Vet.  Med.  Assn.,  52:289-299,  1918,  and  Eeport  Calif. 
Agric.  Exp.  Station  1920-1921.    p.  27. 


1928]  BOVINE    TUBERCULOSIS  19 

One  would  suppose  that  ti^ht  barns  would  be  unnecessary  in  Cali- 
fornia, where  the  cows  can  live  out  of  doors  for  a  greater  length  of 
time  than  in  the  eastern  states,  but  it  must  be  admitted  that  the  cli- 
mate of  the  coast  counties  requires  warm  shelter  for  high-grade  dairy 
cows.  Ventilation  is  a  sanitary  factor  which  in  some  instances  has 
been  neglected.  This  should  be  provided  not  only  in  milking  stables 
but  also  in  the  barns  used  exclusively  for  shelter  and  feeding. 

HOW    CLEANLINESS    HELPS 

The  desirability  of  cleanliness  in  milking,  cooling,  and  transporting 
milk  is  realized  by  all.  Few,  however,  realize  the  significance  of 
cleanliness  as  a  factor  influencing  the  health  of  the  cattle.  Since  the 
manure  of  tuberculous  cattle  often  contains  living  tubercle  bacilli  in 
vast  numbers,  the  importance  of  keeping  it  well  cleaned  out  of  the 
stable  and  corrals  is  readily  seen. 

Stables  should  be  cleaned  out  regularly  and  the  manure  put  where 
it  cannot  be  picked  over  by  hogs  or  cattle.  These  animals  are  easily 
infected  in  that  way.  Cleanliness  also  includes  keeping  the  walls  and 
ceilings  free  from  dirt,  dust  and  cobwebs.  These  are  all  good  resting 
places  for  disease  germs. 

Whitewashing  the  interior  of  the  stable  at  least  twice  a  year  is  a 
great  aid  to  cleanliness  and  also  has  a  distinct  effect  in  destroying 
disease  germs,  especially  when  applied  after  thorough  cleaning.  In 
many  municipalities  dairy  stables  are  required  to  be  whitewashed  at 
regular  intervals.   This  should  be  a  universal  practice. 

HOW   A    HEALTHY    HERD    WAS    BUILT    UP    FROM    ONE    BADLY 

DISEASED 

A  California  dairy  herd,  consisting  of  approximately  800  pure- 
bred and  high-grade  Holstein-Freisian  cows,  had  been  operated  for 
many  years  under  the  handicap  of  extensive  tuberculosis  and  abortion 
disease.  Seven  years  ago  it  was  decided  to  try  to  "breed  out"  these 
diseases.  At  that  time  78  per  cent  of  the  herd  reacted  to  the  tuber- 
culin test  and  28  per  cent  reacted  to  a  blood  test  for  abortion  disease. 
By  removing  the  calves  to  another  farm  and  feeding  them  pasteurized 
milk,  about  1300  healthy  heifers  have  been  raised.  To  April,  1928, 
650  of  these  have  reached  maturity  and  have  given  birth  to  one  or 
more  calves,  and,  in  addition,  about  100  heifers  and  a  large  number 
of  bulls  have  been  sold. 

The  young  animals  were  tuberculin  tested  at  least  once  every  six 
months  and  the  adult  cattle  at  least  once  a  year.    One  and  one-half 


20  CALIFORNIA   AGRICULTURAL   EXTENSION   SERVICE  [ClRC.  21 

per  cent  of  the  calves  reacted  at  the  first  test  and  were  removed.  In 
May,  1927,  about  10  per  cent  of  the  calves  reacted  to  the  test.  This 
was  traced  directly  to  the  carelessness  of  an  unreliable  employee  in 
charge  of  pasteurization.  Very  few  reactions  have  occurred  at  any 
subsequent  test  and  no  definite  tuberculous  lesions  have  been  found 
in  adult  cattle.  On  April  11,  1928,  the  number  being  milked  was  361, 
and  there  were  only  33  head  of  dry  stock.  This  ratio  of  milking  to 
dry  cows   (11:1)  indicates  an  exceptionally  high  degree  of  fertility. 

The  procedure  in  feeding  calves  at  this  dairy  has  been  quite  suc- 
cessful, and,  with  the  exception  of  the  outbreak  in  1927  mentioned 
above,  no  difficulty  has  been  encountered  in  raising  the  calves  on 
pasteurized  milk  heated  to  a  temperature  of  160°  for  twenty  minutes. 

The  cows  calve  in  large  pastures  and  the  calves  are  removed 
between  24  and  48  hours  after  birth.  This  practice  is  more  successful 
than  having  them  calve  in  corrals.  No  colostrum  is  fed  other  than 
that  which  the  calf  may  get  before  it  is  removed.  Colostrum  is  never 
mixed  with  the  milk  to  be  pasteurized.  For  approximately  six  months, 
a  special  eifort  was  made  to  remove  the  calves  as  soon  as  possible  after 
being  dropped.  No  ill  effects  were  observed  even  though  most  of  the 
new-born  did  not  receive  colostrum.  There  then  followed  a  period 
during  which  a  large  number  of  calves  were  unthrifty  and  a  number 
died.  A  change  was  made  and  the  calves  were  allowed  to  remain  with 
their  dams  for  from  24  to  48  hours.  Coincident  with  this  somewhat 
hazardous  procedure,  calves  were  more  satisfactorily  raised,  and  the 
practice  has  been  continued  to  date.  Up  to  the  fifth  or  sixth  week  of 
age,  the  calves  are  fed  pasteurized  whole  milk,  at  which  time  they 
are  gradually  changed  to  reconstituted  skim  milk,  consisting  of  an  8 
per  cent  solution  of  skim  milk  powder  in  warm  water.^- 

The  calves  are  also  given  constant  access  to  ground  oats  to  which 
a  little  salt  is  added.  Bran  and  a  small  quantity  of  coconut  or 
linseed  meal  are  sometimes  added  to  the  oats.  At  the  age  of  three 
or  four  months,  the  calves  are  given  cottonseed  cake  in  small  amounts, 
and  when  they  are  first  turned  out  to  pasture,  at  from  six  to  nine 
months  of  age  (depending  on  the  season  of  the  year),  cottonseed  cake 
in  the  nut  size  is  fed  to  them  in  troughs  or  scattered  over  the  ground. 


12  The  use  of  powdered  skim-milk  is  a  great  convenience  in  raising  calves 
from  tuberculous  dams  because  it  eliminates  the  work  of  pasteurization.  At  the 
University  Experimental  Dairy  in  Berkeley,  it  has  been  possible  to  put  calves 
on  a  reconstituted  liquid  skim  milk  diet  at  five  weeks  of  age,  and  at  eight  weeks 
to  wean  them  to  alfalfa  hay,  and  a  calf  meal  consisting  of  ground  barley  4  parts, 
wheat  bran  3  parts,  dry  skim  milk  3  parts,  salt  1  per  cent.  The  proportion  of  dry 
skim  milk  was  gradually  reduced  in  the  grain  mixture  as  the  calves  aged.  An 
immediately  adjacent  supply  of  water  was  found  necessary  to  assist  the  calves  in 
masticating  the  dry  milk  grain  mixture. 


1928]  BOVINE   TUBERCULOSIS  21 

During  the  first  five  or  six  weeks  the  calves  are  kept  in  small, 
individual  pens  for  the  night  and  part  of  the  day  and,  in  fair  weather, 
they  are  allowed  to  go  into  a  pen  where  they  get  the  full  benefit  of 
the  sunshine.  After  this  period  they  are  moved  into  larger  pens 
where  groups  of  eight  to  ten  are  kept  together.  Following  this  and  at 
further  advanced  ages,  the  groups  are  enlarged  to  fifteen  and  twenty- 
five,  and,  when  first  turned  out  on  pasture,  consist  of  from  thirty 
to  sixty. 

About  95  per  cent  of  all  the  calves  born  normally  during  the  first 
five  years  were  raised  to  maturity.  Calf  disease  lowered  this  percent- 
age to  about  85  in  the  last  two  years.  Conditions  have  now  improved 
and,  by  the  use  of  an  auxiliary  place  and  closing  down  operations 
for  from  thirty  to  forty-five  days  during  the  hot  weather,  this  per- 
centage is  climbing  back  to  normal.  Excellent  housing  facilities  and 
constant  attention  to  cleanliness  have  contributed  to  the  attainment 
of  such  a  low  death  rate. 

From  both  the  financial  and  practical  standpoints,  such  a  plan, 
or  a  similar  one,  may  not  be  feasible  on  many  California  dairies, 
especially  upon  the  smaller  ones.  In  such  cases  it  is  suggested  that 
cooperative  arrangements  be  inaugurated  by  a  group  of  dairymen  for 
developing  clean  herds  from  tuberculous  ones.  The  calves  may  be 
removed  to  a  community  non-infected  farm,  be  cared  for  as  above 
outlined,  and  returned  to  the  owner  after  he  has  disposed  of  his 
infected  stock,  or  the  adult  cows  may  be  removed  to  a  community 
tuberculous  herd  and  the  offspring  returned  to  the  owner  and  reared 
by  him.  In  any  scheme  the  calves  should  be  seperated  from  the  dams 
shortly  after  birth,  be  placed  upon  non-infected  environment  and 
handled  as  outlined  herein.  Plans  involving  cooperation  between 
OAvners  would  be  more  involved  and  the  prospect  of  success  less  cer- 
tain than  in  separate  herds  under  one  management. 

ADVANTAGES  TO   THE   OWNER   OF   A  TUBERCULOSIS-FREE    HERD 

1.  The  reputation  of  the  herd  k  enhanced.  This  is  particularly 
valuable  to  owners  of  pure-bred  stock  and  to  those  who  raise  grade 
milk  stock  for  sale  to  market  milk  dairies.  The  practice  of  buying 
non-reactors  from  tuberculous  herds  has  proved  disappointing 
because,  on  re-test  at  the  point  of  destination  a  proportion  of  such 
animals  are  frequently  found  to  react.  Buyers,  after  such  an  expe- 
rience, quickly  learn  to  avoid  the  tuberculous  herds. 

2.  Markets  are  gradually  closing  to  the  cattle  and  milk  frow. 
tuberculous  herds.    The  Territory  of  Hawaii  will  not  receive  cattle 


22  CALIFORNIA   AGRICULTURAL    EXTENSION    SERVICE  [ClRC.  21 

except  from  accredited  tuberculosis-free  herds  or  from  once-tested  free 
herds.  This  is  simply  one  example  of  the  tendency  to  restrict  the 
movement  of  cattle  from  herds  not  known  to  be  free  from  the  disease. 
This  applies  to  both  reacting:  and  non-reacting  cattle  from  such  herds. 

A  few  years  ago  before  much  progress  was  made  in  the  control 
of  bovine  tuberculosis,  the  advantage  of  having  a  herd  entirely  free 
from  this  disease  was  not  very  evident,  but  the  time  now  appears  to 
be  at  hand  when  the  owners  of  infected  herds  will  either  be  forced 
to  eradicate  the  disease  or  to  operate  under  a  distinct  commercial 
disadvantage.  Some  municipalities  now  demand  that  even  milk 
intended  for  the  pasteurized  milk  trade  must  come  from  cattle  which 
pass  the  tuberculin  test  and  show  no  physical  evidence  of  tuberculosis. 
It  is  probable  that  many  more  communities  will  soon  insist  upon 
similar  requirements. 

3.  Tuhercidous  herds  show  heavy  losses.  Sickness  tends  to  increase 
in  proportion  to  the  development  of  tuberculous  infection  in  a  herd. 
In  herds  where  only  a  small  percentage  of  the  cattle  react,  such  losses 
may  hardly  be  noticeable.  In  heavily  infected  herds,  there  is  a  loss, 
not  only  through  the  obviously  direct  wasting  or  fatal  effect  of  the 
disease,  but  also  from  ailments  not  attributed  by  the  owner  to  tuber- 
culosis, such  as  chronic  mammitis,  sterility,  indigestion,  diarrhea, 
chronic  bloating  and  abscesses. 

THE   ACCREDITED    HERD    PLAN 

Official  recognition  for  herds  that  are  free  from  tuberculosis  may 
be  arranged  by  owners  of  such  herds  by  complying  with  certain  state 
and  federal  rules.  These  rules  define  a  tuberculosis-free  accredited 
herd  as  one  in  which  no  animal  affected  with  tuberculosis  has  been 
found  upon  two  annual  or  three  semi-annual  tuberculin  tests,  and 
by  physical  examination,  applied  by  a  regularly  employed  veter- 
inarian of  the  United  States  Bureau  of  Animal  Industry  or  of  the 
state  in  which  cooperative  tuberculosis  eradication  work  is  conducted 
by  the  United  States  Department  of  Agriculture  and  the  state;  or 
one  in  which  no  animal  affected  with  tuberculosis  has  been  found 
upon  two  annual  or  three  semi-annual  tuberculin  tests  applied  by  an 
accredited  and  a  federal  or  state  veterinarian. 

Information  concerning  the  methods  and  rules  for  the  establish- 
ment and  maintenance  of  tuberculosis-free  accredited  herds  of  cattle 
in  California  may  be  obtained  by  writing  to  the  California  State 
Department  of  Agriculture,  Sacramento,  or  to  the  Inspector  in 
Charge,  United  States  Bureau  of  Animal  Industry,  Federal  Building, 
Sacramento. 


1928]  BOVINE    TUBERCULOSIS  23 


THE  CALIFORNIA  TUBERCULOSIS   FREE-AREA   LAW 

By  the  terms  of  the  California  Statutes  of  1927,  Chapter  47,  any 
county  having  not  more  than  10  per  cent  of  its  cattle  infected  with 
tuberculosis  as  shown  by  the  records  of  the  State  Department  of 
Agriculture,  may  obtain  the  cooperative  assistance  of  the  state  and 
federal  departments  of  agriculture  in  eradicating  the  malady.  A 
survey  to  determine  the  percentage  of  reactors  is  not  extended  to  any 
county  unless  requested  through  the  county  supervisors.  When  a 
county  survey  has  been  started  by  the  California  Department  of 
Agriculture,  the  tuberculin  testing  of  all  cattle  in  the  county  becomes 
compulsory. 

According  to  officials  of  the  California  Department  of  Agriculture, 
when  the  enactment  of  the  free-area  law  was  under  consideration, 
the  subject  of  indemnity  for  the  slaughter  of  reacting  cattle  was  given 
careful  thought.  The  conclusion  was  reached  that,  under  prevailing 
conditions  in  California  at  that  time,  indemnity  by  the  state  would 
not  be  practicable. 


THE    ADVANTAGES    OF    MODIFIED    ACCREDITED    AREAS 

Dairy  and  breeding  cattle  of  good  quality  in  areas  free  from 
bovine  tuberculosis  find  a  ready  sale.  Buyers  seek  those  sections 
which  have  a  reputation  for  healthy  stock  and  the  United  States 
Bureau  of  Animal  Industry  has  reported  marked  activity  in  inter- 
state shipments  of  high-class  cattle  from  modified  accredited  areas  in 
various  parts  of  this  country.  Such  areas  have  been  defined  by  the 
United  States  Department  of  Agriculture  as  those  in  which  a  com- 
plete official  tuberculin  test  of  all  cattle  shows  less  than  %  of  1  per 
cent  reactors,  and  which  otherwise  comply  with  regulations  promul- 
gated by  the  department. 

Increase  in  the  selling  value  of  both  cattle  and  hogs  as  compared 
with  neighboring  counties  has  followed  the  establishment  of  modified 
areas.  In  some  sections  the  meat  packing  companies  return  a  bonus 
of  10  per  cent  on  all  hogs  from  modified  areas  which  do  not  show 
lesions  of  tuberculosis.  The  Live  Stock  Commissioner^^  of  the  National 
Live  Stock  Exchange,  Chicago,  reports  that  in  Hillsdale  County, 
Michigan,  after  accreditation,  the  farmers  received  an  average  of 
twenty-five  dollars  a  head  more  than  the  selling  price  of  cows  of  the 


13  Smith,  H,  E.    Tuberculosis  as  a  livestock  problem  in  tlie  middle  west.    Jour. 
Amer.  Vet.  Med.  Assn.  69:290-296.    1926. 


24  CALIFORNIA   AGRICULTURAL   EXTENSION   SERVICE  [CiRC.  21 

same  quality  in  the  adjoining  county.  Cattle  may  be  shipped  from 
an  accredited  county  to  any  point  in  the  United  States  without  the 
inconvenience  or  expense  of  a  tuberculin  test  at  the  time  of  shipment. 
The  accredited  herd  work  is  conducted  cooperatively  by  the  state  and 
federal  departments  of  agriculture. 


COUNTY  LEGISLATION 

Progress  in  the  control  of  bovine  tuberculosis  has  been  made  in 
the  southern  part  of  this  state  through  county  ordinances.  County 
tuberculosis  eradication  efforts,  if  operated  independently  of  state 
and  federal  support,  should  not  be  expected  to  accomplish  much 
unless  they  are  well  organized  and  liberally  financed  over  a  long 
period  of  time.  Local  tuberculosis  ordinances  should  be  carefully 
worded  and  limited  to  provisions  which  can  be  effectively  enforced. 


STATE    AND    FEDERAL    INDEMNITIES 

Provision  is  made  in  many  states  for  the  reimbursement  of 
owners  for  losses  in  building  up  accredited  tuberculosis-free  herds. 
These  usually  are  in  the  form  of  indemnities  as  follows: 

(1)  The  owner,  in  applying  for  accreditation,  agrees  to  permit 
the  slaughter  of  all  reactors  to  the  tuberculin  test. 

(2)  The  dairy  value  of  the  reacting  cattle  is  determined  by  a 
board  of  appraisers. 

(3)  The  reacting  cattle  are  killed  for  beef  at  a  slaughter-house 
having  official  meat  inspection.  If  only  slight  lesions  are  found  which 
do  not  involve  an  edible  part,  the  carcass  is  passed  as  fit  for  food.  If 
extensive  lesions  are  present  there  may  still  be  some  salvage  value  in 
processing  the  carcass  for  fertilizer. 

(4)  The  loss  represented  by  the  difference  between  the  appraised 
value  and  the  salvage  is  usually  shared  equally  by  the  owner,  the 
state  and  the  federal  government.  Some  states  assume  two-thirds  of 
the  loss  and  the  federal  government  the  balance. 

For  several  years  the  United  States  Congress  has  appropriated 
annually  several  million  dollars  for  such  indemnities,  but  they  are 
only  available  in  states  where  provision  is  made  for  supplementary 
indemnities  by  the  state.  In  California,  indemnity  provision  cannot 
be  made  by  the  state  because  of  limitations  placed  on  the  Legislature 
by  the  present  state  constitution;  besides,  indemnities  have  not  been 
very  urgently  needed  in   California  since  it  is  not  compulsory   to 


1928]  BOVINE   TUBERCULOSIS  25 

slaughter  tuberculin  reacting  animals  in  this  state.  There  have,  how- 
ever, been  instances  in  the  course  of  establishing  tuberculosis-free 
areas  where  indemnities  would  have  facilitated  the  work. 

Government  indemnities  not  only  save  cattle  owners  from  part  of 
the  loss  forced  upon  them  by  official  eradication  measures,  but  also 
tend  to  pacify  objectors  and  reduce  opposition.  In  some  states  it  has 
been  observed  that  indemnities  have  a  favorable  effect  on  public 
sentiment  in  general  that  is  helpful  to  bovine  tuberculosis  eradication 
programs. 

THE  TOWNSHIP   FREE-AREA   METHOD 

In  California  no  attempt  has  yet  been  made  to  carry  out  the 
tuberculosis-free  area  plan  on  units  smaller  than  a  county.  Neverthe- 
less, it  would  seem  appropriate  to  include  in  this  circular  a  description 
of  what  is  being  done  in  New  York  State. 

According  to  E.  T.  Faulder^*,  director  of  the  New  York  State 
Bureau  of  Animal  Industry,  practically  all  tests  in  that  state  are 
made  by  the  township  area  method.  Testing  is  not  inaugurated  in 
any  township  until  approximately  90  per  cent  of  the  cattle  owners 
have  first  signed  the  accredited  herd  agreement,  or  90  per  cent  of 
the  cattle  in  the  township  are  represented  in  the  sign-up.  Townships 
having  the  highest  percentage  signed  are  tested  first  and  as  many  are 
tested  during  the  year  as  the  available  indemnity  funds  will  permit. 
In  New  York  on  March  1,  1928,  all  of  the  cattle  had  been  tested  in 
449  townships,  covering  47  per  cent  of  the  area  of  the  state.  Indemnity 
funds  are  available  from  state  appropriations  in  New  York  for  90 
per  cent  of  the  appraised  value,  not  to  exceed  $90.00  for  a  grade 
animal  or  $150.00  for  a  registered  pure-bred  animal,  such  registration 
to  have  taken  place  before  the  date  of  appraisal. 

The  salvage  proceeds  derived  from  the  sale  of  the  carcass  are  paid 
directly  to  the  owner  by  the  purchaser  and  are  deducted  from  the 
appraised  value,  becoming  a  part  of  the  amount  of  indemnity  due,  the 
owner  receiving  from  the  state  the  difference  between  the  appraised 
value  and  the  salvage  value  up  to  $90.00  for  a  grade  animal  and 
$150.00  for  a  registered  pure-bred  animal.  The  balance,  if  any,  is 
paid  by  the  federal  government  not  to  exceed  $25.00  for  a  grade 
animal  or  $50.00  for  a  registered  pure-bred  animal.  In  no  case  can 
an  owner  receive  as  indemnities  from  all  sources — salvage,  state  and 
federal — an  amount  exceeding  the  appraised  value. 


14  Faulder,   E.   T.    Help   eradicate  tuberculosis.    N.   Y.   State  Dept.   Agr.   Cir. 
350:1-26.    1926. 


26  CALIFORNIA   AGRICULTURAL   EXTENSION    SERVICE  [ClRC.  21 


WHY   REACTING   CATTLE    MUST   BE    BRANDED   WITH    A    "T" 

The  prime  object  in  branding  reacting  cattle  on  the  jaw  with  the 
letter  T,  as  required  by  California  statutes,  1927,  chapter  47,  is  to  pre- 
vent tuberculosis  animals  from  being  moved,  by  purchase  or  other- 
wise, into  tuberculosis-free  herds.  As  long  as  recognized  tuberculous 
herds  exist  and  official  permission  can  be  obtained  to  remove  the  tuber- 
culin reacting  cattle  to  such  herds,  the  reacting  animals  should  have 
a  fair  dairy  value  which  is  usually  greater  than  that  covered  by 
indemnity  in  most  states. 

One  year's  experience  under  the  present  California  bovine  tuber- 
culosis law  has  shown  that  the  placing  of  a  T  brand  on  the  jaw  has 
caused  an  unjust  depreciation  in  the  sale  value  of  the  animal.  In 
many  instances  beef  buyers  have  taken  advantage  of  the  brand  to 
reduce  the  price.  Losses  may  be  avoided  to  some  extent  by  selling 
such  animals  on  commission  through  a  slaughter  house  having  official 
meat  inspection. 

Figures  tabulated  by  the  United  States  Bureau  of  Animal  Indus- 
try show  that  the  salvage  received  by  certain  original  owners  for 
tuberculous  cattle  killed  in  slaughter  houses  on  a  commission  basis 
averaged  more  than  50  per  cent  higher  than  from  similar  cattle  killed 
after  having  passed  through  the  hands  of  one  or  more  buyers. 

This  tendency  to  take  advantage  of  the  presence  of  the  T  brand 
to  beat  down  the  price  has  been  limited,  we  believe,  to  small  dealers. 


THE  ORDERLY  MARKETING  OF   REACTING   CATTLE 

The  large  firms  in  control  of  the  meat  packing  industry  in  the 
central  states  have  cooperated  in  many  ways  to  promote  tuberculosis 
eradication  and  in  California  similar  cooperation  could  doubtless  be 
expected  both  from  packers  and  from  existing  organizations  for 
orderly  marketing.  The  Manager  of  the  Western  Cattle  Marketing 
Association  has  assured  the  writers  that  that  organization  would  be 
at  the  service  of  any  officially  recognized  and  properly  constituted 
effort  to  market  reacting  dairy  cattle  for  beef. 

The  present  relatively  high  value  of  dairy  cattle  for  beef  will  more 
than  offset  in  many  instances  the  disadvantage  in  California  of  the 
lack  of  state  and  federal  reimbursement  funds  since  federal  regula- 
tions limit  appraisals  to  $75  a  head  for  grade  cattle  and  $125  a  head 
for  pure-bred  animals. 


1928]  BOVINE   TUBERCULOSIS  27 

Since  the  eradication  of  tuberculosis  is  a  problem  of  importance 
in  financial  as  well  as  livestock  circles,  it  would  seem  appropriate  for 
all  the  business  interests  concerned  to  participate  in  a  plan  for  the 
orderly  marketing  of  reacting  and  branded  cattle. 

In  a  statewide  campaign  of  bovine  tuberculosis  eradication,  the 
flow  of  reacting  cattle  to  slaughter  could  be  regulated  to  some  extent 
by  modifying  the  numbers  tested  in  accordance  with  market  condi- 
tions or  arranging  to  hold  and  feed  such  animals  with  a  view  to 
getting  as  much  as  possible  in  beef  value. 


THE    NEED    FOR    TUBERCULOSIS-FREE    CATTLE    IN    CALIFORNIA 

According  to  the  report  of  the  Los  Angeles  County  Live  Stock 
Department  for  the  year  ending  June  30,  1927,  approximately  twenty 
thousand  dairy  cows  were  added  to  the  herds  of  that  county  during 
the  year.  Thirteen  thousand,  or  about  65  per  cent,  of  the  cattle  were 
purchased  in  dairy  districts  outside  the  state  of  California.  If  cattle 
breeders  in  the  central  and  northern  parts  of  this  state  had  been  in 
position  to  meet  the  Los  Angeles  County  requirements,  over  one 
million  and  a  half  dollars  from  that  one  county  alone  could  have  been 
spent  within  the  state.  There  is  a  real  need  in  California  for  expan- 
sion in  the  production  of  disease-free,  high-grade  heifers. 


STATION  PUBLICATIONS  AVAILABLE  FOR  FREE  DISTRIBUTION 


BULLETINS 
No. 


No. 

253.   Irrigation   and   Soil   Conditions  in  the  3  89. 

Sierra   Nevada   Foothills,    California.  390, 

262.  Citrus   Diseases   of   Florida   and    Cuba 

Compared   with   those   of    California.  391, 

263.  Size  Grades  for  Ripe  Olives. 

268.   Growing  and  Grafting  Olive  Seedlings,  392. 

277.  Sudan  Grass.  393. 

278.  Grain   Sorghums.  394. 

279.  Irrigation   of   Rice  in    California. 
283.  The  Olive  Insects  of  California. 

304.   A  Study  of  the  Effects  of  Freezes  on  395. 

Citrus  in  California. 

310.   Plum  Pollination.  396. 

313.  Pruning      Young      Deciduous      Fruit 

Trees.  397. 

324.   Storage  of  Perishable  Fruits  at  Freez- 
ing Temperatures.  398. 

328.   Prune    Growing  in    California,  400. 

331.   Phylloxera-resistant   Stocks.  402. 

335.   Cocoanut   Meal    as    a    Feed    for    Dairy  404. 

Cows   and    Other   Livestock.  405. 

340.   Control     of     the     Pocket     Gopher     in  406. 

California.  407. 

343.  Cheese   Pests  and  Their   Control. 

344.  Cold    Storage   as   an    Aid   to   the   Mar- 

keting of  Plums,  a  Progress  Report.  4  08. 

347.  The  Control  of  Red  Spiders  in  Decid-  409. 

nous  Orchards. 

348.  Pruning  Young  Olive  Trees. 

349.  A     Study    of     Sidedraft    and    Tractor 

Hitches.  410. 

350.  Agriculture      in      Cut-Over      Redwood 

Lands. 

353.  Bovine    Infectious    Abortion,    and    As-  411. 

sociated  Diseases  of  Cattle  and  New- 
born  Calves.  412. 

354.  Results  of  Rice  Experiments  in   1922. 

357.  A    Self-Mixing    Dusting    Machine    for 

Applying  Dry  Insecticides  and  Fun-  414. 

gicides. 

358.  Black    Measles,     Water    Berries,     and  415. 

Related  Vine  Troubles.  416. 

361.  Preliminary  Yield   Tables  for   Second- 

Growth    Redwood.  417. 

362.  Dust  and   the  Tractor   Engine. 

363.  The  Pruning  of  Citrus  Trees  in   Cali-  418. 

fornia. 

364.  Fungicidal    Dusts    for    the    Control    of  419. 

Bunt. 

366.  Turkish     Tobacco     Culture,     Curing,  420. 

and   Marketing. 

367.  Methods  of  Harvesting  and  Irrigation  421. 

in  Relation  to  Moldy  Walnuts.  422. 

368.  Bacterial      Decomposition     of      Olives 

During  Pickling.  423. 

369.  Comparison      of     Woods     for     Butter 

Boxes.  424. 

370.  Factors    Influencing   the    Development 

of  Internal  Browning  of  the  Yellow  425. 

Newton   Apple.  426. 

3  71.   The    Relative    Cost    of    Yarding    Small 

and   Large   Timber.  427. 

373.  Pear    Pollination. 

374.  A    Survey    of    Orchard    Practices    in  428. 

the     Citrus     Industry     of     Southern 
California. 

375.  Results   of    Rice    Experiments   at    Cor-  429. 

tena,   1923,  and  Progress  in  Experi-  430. 

ments  in  Water  Grass  Control  at  the  431. 

Biggs   Rice   Field    Station,    1922-23. 
377.   The  Cold  Storage  of  Pears.  432. 

380.   Growth    of    Eucalyptus    in    California 

Plantations.  433. 

382.   Pumping    for    Draininge    in    the    San 

Joaquin   Valley,    California.  434. 

385.  Pollination  of  the  Sweet  Cherry. 

386.  Pruning     Bearing      Deciduous     Fruit  435. 

Trees. 

3  87.   Fig    Smut. 

388.  The   Principles   and   Practice   of    Sun- 
Drying  Fruit. 


Berseem  or  Egyptian  Clover. 

Harvesting  and  Packing  Grapes  in 
California. 

Machines  for  Coating  Seed  Wheat 
with   Copper   Carbonate   Dust, 

Fruit  Juice  Concentrates. 

Crop   Sequences  at  Davis, 

I.  Cereal  Hay  Production  in  Cali- 
fornia. II.  Feeding  Trials  with 
Cereal  Hays. 

Bark  Diseases  of  Citrus  Trees  in  Cali- 
fornia. 

The  Mat  Bean,  Phaseolus  Aconitifo- 
lius. 

Manufacture  of  Roquefort  Type  Cheese 
from  Goat's  Milk. 

Orchard    Heating   in    California. 

The   Utilization  of  Surplus  Plums. 

The  Codling  Moth  in  Walnuts. 

The  Dehydration  of  Prunes. 

Citrus    Culture   in    Central    California. 

Stationary  Spray  Plants  in  California. 

Yield,  Stand,  and  Volume  Tables  for 
White  Fir  in  the  California  Pine 
Region. 

Alternaria   Rot  of   Lemons. 

The  Digestibility  of  Certain  Fruit  By- 
products as  Determined  for  Rumi- 
nants. Part  I.  Dried  Orange  Pulp 
and  Raisin   Pulp. 

Factors  Influencing  the  Quality  of 
Fresh  Asparagus  after  it  is  Har- 
vested. 

Paradichlorobenzene  as  a  Soil  Fumi- 
gant. 

A  Study  of  the  Relative  Value  of  Cer- 
tain Root  Crops  and  Salmon  Oil  as 
Sources   of    Vitamin    A   for   Poultry. 

Planting  and  Thinning  Distances  for 
Deciduous  Fruit  Trees. 

The  Tractor  on   California  Farms. 

Culture  of  the  Oriental  Persimmon  in 
California. 

Poultry  Feeding:  Principles  and  Prac- 
tice. 

A  Study  of  Various  Rations  for  Fin- 
ishing Range  Calves    as  Baby  Beeves. 

Economic  Aspects  of  the  Cantaloupe 
Industry. 

Rice  and  Rice  By-Products  as  Feeds 
for  Fattening  Swine. 

Beef   Cattle   Feeding   Trials,    1921-24. 

Cost  of  Producing  Almonds  in  Cali- 
fornia :   a  Progress  Report. 

Apricots  (Series  on  California  Crops 
and   Prices). 

The  Relation  of  Rate  of  Maturity  to 
Egg  Production. 

Apple  Growing   in   California. 

Apple  Pollination  Studies  in 
fornia. 

The  Value  of  Orange  Pulp  for  Milk 
Production, 

The  Relation  of  Maturity  of 
fornia  Plums  to  Shipping 
Dessert  Quality. 

Economic  Status  of  the  Grape  Industry. 

Range  Grasses  of  California. 

Raisin  By-Products  and  Bean  Screen- 
ings as  Feeds  for  Fattening  Lambs. 

Some  Economic  Problems  Involved  in 
the  Pooling  of  Fruit. 

Power  Requirements  of  Electrically 
Driven     Manufacturing    Equipment. 

Investigations  on  the  Use  of  Fruits  in 
Ice  Cream  and  Ices. 

The  Problem  of  Securing  Closer 
Relationship  Between  Agricultural 
Development  and  Irrigation  Con- 
struction. 


Cali- 


Cali- 
and 


BULLETINS — (Oontinued) 


No. 
436. 

437. 

438. 

439. 


440. 


441. 
442. 
443. 

444. 


No. 
87. 
117. 

127. 
129. 
136. 

144. 

157. 
164. 
166. 
178. 
202. 

203. 
209. 
212. 
215. 
230. 

231. 
232. 

234. 

238. 
239. 

240. 

241. 

243. 

244. 
245. 
248. 

249. 
250. 

252. 
253. 
255. 

257. 

258. 
259. 
261. 


I.  The  Kadota  Fig.  II.  Kadota  Fig 
Products. 

Economic  Aspects  of  the  Dairy  In- 
dustry. 

Grafting  Affinities  with  Special  Refer- 
ence to  Plums. 

The  Digestibility  of  Certain  Fruit  By- 
products as  Determined  for  Rumi- 
nants. Part  II.  Dried  Pineapple 
Pulp,  Dried  Lemon  Pulp,  and  Dried 
Olive  Pulp. 

The  Feeding  Value  of  Raisins  and 
Dairy  By-Products  for  Growing  and 
Fattening  Swine. 

The  Electric  Brooder. 

Laboratory  Tests  of  Orchard  Heaters. 

Standardization  and  Improvement  of 
California   Butter. 

Series  on  California  Crops  and  Prices: 
Beans. 


No. 

445.  Economic    Aspects    of    the    Apple    In- 

dustry. 

446.  The  Asparagus  Industry  in  California. 

447.  The  Method  of  Determining  the  Clean 

Weights    of    Individual    Fleeces    of 
Wool. 

448.  Farmers'      Purchase     Agreement     for 

Deep   Well   Pumps. 

449.  Economic   Aspects  of  the  Watermelon 

Industry. 

450.  Irrigation    Investigations    with    Field 

Crops  at  Davis,  and  at  Delhi,   Cali- 
fornia. 

451.  Studies    Preliminary   to   the   Establish- 

ment of  a  Series  of  Fertilizer  Trials 
in  a  Bearing  Citrus  Grove. 

452.  Economic    Aspects    of    the    Pear    In- 

dustry. 


CIRCULARS 
No. 

Alfalfa.  265. 

The    selection    and    Cost    of    a    Small  266. 

Pumping  Plant. 

House  Fumigation.  267. 
The  control  of  Citrus  Insects. 

Melilotus    Indica    as    a    Green-Manure  269. 

Crop  for  California.  270. 

Oidium    or    Powdery    Mildew    of    the  273. 

Vine.  276. 

Control  of   Pear   Scab.  277. 
Small   Fruit   Culture   in   California. 

The  County  Farm   Bureau.  278. 
The  Packing  of  Apples  in   California. 

County    Organization    for    Rural    Fire  279. 

Control. 

Peat   as   a   Manure   Substitute.  281. 
The  Function  of  the  Farm  Bureau. 
Salvaging  Rain-Damaged   Prunes. 

Feeding  Dairy   Cows  in   California.  282. 
Testing   Milk,    Cream,   and   Skim  Milk 

for  Butterfat.  284. 

The   Home  Vineyard.  286. 

Harvesting    and    Handling    California  287. 

Cherries    for    Eastern    Shipment.  288. 

Winter     Injury     to     Young     Walnut  289. 

Trees  During  1921-1922.  290. 

The   Apricot  in   California.  292. 

Harvesting     and     Handling     Apricots  293. 

and  Plums  for  Eastern  Shipment.  294. 

Harvesting    and    Handling    California  296. 

Pears  for  Eastern  Shipment. 

Harvesting    and    Handling    California  298. 

Peaches  for  Eastern   Shipment. 

Marmalade     Juice     and     Jelly     Juice  300. 

from  Citrus  Fruits.  301. 

Central  Wire  Bracing  for  Fruit  Trees.  302. 

Vine  Pruning   Systems.  304. 

Some  Common   Errors  in   Vine   Prun-  305. 

ing  and  Their  Remedies.  307. 

Replacing  Missing  Vines.  308. 

Measurement   of   Irrigation    Water   on  309. 

the  Farm.  310. 
Support  for   Vines. 

Vineyard   Plans.  311. 

Leguminous    Plants    as    Organic    Fer-  312. 

tilizers   in    California    Agriculture. 
The  Small-Seeded   Horse  Bean    (Vicia 

faba   var.   minor). 
Thinning   Deciduous  Fruits. 
Pear  By-Products. 
Sewing  Grain  Sacks. 


Plant   Disease  and   Pest  Control. 

Analyzing  the  Citrus  Orchard  hy 
Means  of  Simple  Tree  Records. 

The  Tendency  of  Tractors  to  Rise  in 
Front;  Causes  and  Remedies. 

An   Orchard   Brush   Burner. 

A  Farm  Septic  Tank. 

Saving  the  Gophered  Citrus  Tree. 

Home   Canning. 

Head,  Cane  and  Cordon  Pruning  of 
Vines. 

Olive  Pickling  in  Mediterranean 
Countries. 

The  Preparation  and  Refining  of 
Olive  Oil  in  Southern  Europe. 

The  Results  of  a  Survey  to  Deter- 
mine the  Cost  of  Producing  Beef  in 
California. 

Prevention  of  Insect  Attack  on  Stored 
Grain. 

The  Almond  in   California. 

Milk  Houses  for  California  Dairies. 

Potato   Production  in   California. 

Phylloxera  Resistant  Vineyards. 

Oak  Fungus  in   Orchard   Trees. 

The  Tangier  Pea. 

Alkali   Soils. 

The    Basis   of   Grape    Standardization. 

Propagation   of   Deciduous  Fruits. 

Control  of  the  California  Ground 
Squirrel. 

Possibilities  and  Limitations  of  Coop- 
erative Marketing. 

Coccidiosis  of  Chickens. 

Buckeye  Poisoning  of  the  Honey  Bee. 

The   Sugar  Beet  in  California. 

Drainage  on  the  Farm. 

Liming  the   Soil. 

American  Foulbrood  and  Its  Control. 

Cantaloupe   Production   in   California. 

Fruit  Tree  and   Orchard  Judging. 

The  Operation  of  the  Bacteriological 
Laboratory  for  Dairy  Plants. 

The  Improvement  of   Quality  in  Figs. 

Principles  Governing  the  Choice,  Op- 
eration and  Care  of  Small  Irrigation 
Pumping  Plants. 


The  publications  listed  above  may  be  had  by  addressing 

College  of  Agriculturey 

University  of  California, 
8m-9.'28  Berkeley,  California. 


